In the manufacture and assembly of windows and doors that include a viewing or vision area; a viewing area layer (typically constructed of glass) must be assembled to a sash and fixedly secured thereto. More specifically, a traditional window and door manufacturing technique requires a number of steps. First, the sash, window frame or door glass assembly must be constructed. FIG. 1 illustrates an embodiment of a window sash 20. The window sash includes a sash opening 26 and a glazing leg 22 (best seen in FIGS. 6 and 7) to which a viewing area or glass layer 24 is ultimately secured. The glazing leg 22 extends inwardly from an inner surface of the window sash 20, along a perimeter of sash opening 26. Once the sash assembly is constructed, a suitable back bedding glazing compound is applied to the glazing leg 22. Next, the viewing area or glass 24 is laid into sash 20, and into contact with the back bedding glazing compound. A typical back bedding glazing compound used in this process has an open time that begins upon application, before the glass is laid, and can range from minutes to hours.
The length of cure time for the back bedding glazing compound cure time in prior art systems is necessary due to the steps involved in applying the back bedding glazing compound and properly laying and positioning the glass into the sash. More specifically, the glass laying process is a multi-step process.
After the back bedding glazing compound is applied to the glazing leg, setting blocks may be installed along the perimeter of the sash opening 26 so as to assist with centering, or squaring the glass layer 24 in the sash opening 26. After the setting blocks are positioned, the glass layer 24 is placed in contact with the back bedding glazing compound along the glazing leg, compressing the back bedding glazing compound to effect a strong seal between the glass layer an the glazing leg. In some instances, it may be necessary to maneuver the glass layer to properly center or square the glass layer in the sash. Alternatively, after the back bedding glazing compound is applied to the glazing leg, the glass is laid and centered in the sash opening and setting blocks are inserted around the glass perimeter. Accordingly, a sufficient cure time for the back bedding glazing compound has been required to provide for such maneuverability.
Once the glass layer 24 is properly positioned, glazing beads (or glazing stops) may be installed such that they conceal a gap created by the setting blocks to maintain position of the glass while the back bedding glazing compound cures to fix the glass layer 24 to the glazing leg 22. However, because of the cure time needed to accommodate proper positioning of the glass layer on the back bedding glazing compound, once the glass layer 24 is positioned with the spacers, the assembly must then be moved to a curing station to complete the cure operation. As such, the current method results in significant delay in completing manufacturing of windows and doors. In addition, due to the extra manufacturing steps of loading and unloading the assembly onto drying pallets, significant expense is incurred.
Accordingly, there exists a need to decouple the back bedding glazing compound open time limitations from the glass laying process. Decoupling will allow for the use of back bedding glazing compounds with faster cure times, thereby allowing increased through put while reducing, eliminating staging and racking time of glazed sashes.